Pulmonary dirofilariasis with serologic study on familial infection with Dirofilaria immitis.

An asymptomatic patient with a pulmonary coin lesion surgically diagnosed with pulmonary dirofilariasis caused by infection with Dirofilaria immitis (D. immitis) is presented. The preoperative stored serum of the patient was positive for D. immitis by enzyme-linked immunosorbent assay (ELISA). A family study showed that three of five family members were seropositive for D. immitis. These results suggest that family members of a patient with pulmonary dirofilariasis were frequently exposed to D. immitis and serodiagnostic methods are useful for detecting subclinical infection of D. immitis.